1. Learning Outcomes
Find the perimeter of 2-D composite shape of
two or more quadrilaterals and triangles.
2. Find the area of a 2-D composite
shape of two or more quadrilaterals and
triangles.
3. Solve problems in real context
involving calculation of perimeter and area
of 2-D shapes

2. Revision for 2 Dimensional Shapes
A perimeter is the total
length of the outer sides
of a shape
Area is the size
of a flat surface
8 cm × 3 cm = 24cm²
Formula : Area = length x breadth
Unit of area : square centimetre (cm²) and square metre ( m²)
Area of triangle : Base × Height
4 cm height 2
base
3 cm

3. Find the perimeter of 2-D composite shape of two or more
quadrilaterals and triangles.
Example 1 :
8 cm
10 cm
6 cm
Diagram 1
Find the perimeter, in cm, of the above diagram.
Recognize all the 10
given lengths of
certain sides
8 cm
10 cm
Step 1 :
6 cm
10
Total all the
Step 2 :
distance
10 + 10 + 10 + 8 + 6 =
around the
diagram
= 44 cm
REMEMBER …..
A perimeter is the total length of the
outer sides of the shape

4. Find the area of a 2-D composite shape of two or more
quadrilaterals and triangles.
Example 1
8 cm
10 cm
6 cm
Diagram 3
Diagram 3 shows a square and rectangle. Find the
area, in cm², of the whole diagram.
Recognize the length
and dimension of the
given shape Height
8 cm
10 cm A
Step 1 : B
Breadth
Length 6 cm
Base
Square =
Step 2 : Length × Breadth
A = 10 × 10 = 100 cm². Triangle =
Base × Height
B = 6 × 10 ÷ 2 = 30 cm². 2
Step 3 :
Area of the diagram
=A+B
= 100 cm² + 30 cm²
Total up
= 130 cm².
Example 1
8 cm
Diagram 3
Diagram 3 shows a two equal triangles and a square.
Find the perimeter, in cm of the whole diagram.

5. 10 cm
6 cm
Step 1 :
Understanding
the problem
• To find the perimeter of the
diagram.
• Given the lengths of certain sides
Devise a plan
Step 2 :
using formula
• Label the whole diagram
for calculating
Perimeter = total distance
perimeter
outside edge around the
diagram
Carry out Step 3 :
the plan
Perimeter = (10 + 8 + 10 + 6 + 8 + 6) cm
= 48 cm.
Checking the
Step 4 : solution
Make sure the calculation is correct.
Add only all the outside edges of the
diagram.

6. Example 2
6 cm
4 cm
The diagram shows a two equal square and a right angled
triangle. Find the area, in cm², of the whole diagram.
Step 1 :
Understanding
the problem
To find the area of the diagram.
The side of the square = 4 cm
The based of the triangle = 8 cm
Devise a plan
Step 2 :
using formula
for calculating
Area of square = length × breadth
area
Area of triangle = base × height
2
Step 3 :
Carry out Area of square = (4 × 4) × 2 = 32 cm²
the plan Area of triangle = 8 × 6 ÷ 2 = 24 cm²
Total area = 32 cm² + 24 cm²
= 56 cm²
Checking the
Step 4 : solution
Make sure the calculation is correct.